I recently bought a project and I am having a heck of a time decoding the stamped number on the block The block casting number on the back of the engine drivers side is 3963512 which comes up as a 1969 427 or a 1970-75 454 but the stamped number on the front of the block passenger side is T07247BG and that doesn't seem to jive with anything I have found on any online decoders? especially the 7BG suffix code ? all the numbers are in plain sight and clear as day. any ideas? The engine is in a '28 Ford of all things and also has aluminum heads, casting number: 3946074 which came on high horse 427's like L88's and a factory GM aluminum manifold 3933163 which is from the same era. I don't know much about big block Chevs, and am just going by what I have found on line.